The subject matter disclosed herein relates to a method and device for automatically identifying a point of interest in a depth measurement on a viewed object using a video inspection device.
Video inspection devices, such as video endoscopes or borescopes, can be used to take depth measurements on an object (e.g., lowest points in anomalies such as pits or dents, heights of welds, measurements of offsets or clearances between surfaces, etc.). In many instances, the surface of the object is inaccessible and cannot be viewed without the use of the video inspection device. For example, a video inspection device can be used to inspect the surface of a blade of a turbine engine on an aircraft or power generation unit to identify any anomalies to determine if any repair or further maintenance is required. In order to make that assessment, it is often necessary to obtain highly accurate-dimensional measurements of the surface to verify that the anomaly does not fall outside an operational limit or required specification for that object.
A video inspection device can be used to obtain and display a two-dimensional image of the surface of a viewed object to determine the depth measurement. This two-dimensional image of the surface can be used to generate three-dimensional data of the surface that provides the three-dimensional coordinates (e.g., (x, y, z)) of a plurality of points on the surface. In some video inspection devices, a depth measurement is determined by placing three cursors one at a time on a the surface of the object to establish a reference plane and then a fourth cursor at a point not on the plane to determine the perpendicular distance between the reference surface and the surface at the fourth point. Accordingly, the user has to move the fourth cursor around to find the point of interest on the surface to measure, e.g., the deepest point, the highest point, or the smallest clearance distance. This process can be time consuming and may not always result in the point of interest being identified in a depth measurement.